The use of mice as a model system for acute renal failure is being adopted by many members of the renal community, especially in combination with transgenic and/or gene knockout technologies. Many of the projects that will be part of our program will use gene knockouts in mice for comparison with wild-type littermates before and after acute renal failure. Because of our desire to be able to make easier cross comparisons between pathways elucidated in the various projects, we have decided to use mice as the model system for most of our studies. This pooling of resources should also provide greater efficiency of availability to the mice and greater savings of labor and cost since all of the investigators will not have to become technically proficient in the maintenance and manipulation of the mice during breeding and surgery. The core facility will provide maintenance, breeding, and record keeping for the various mouse colonies described by the investigators. It will provide personnel for animal surgery to ensure uniformity in the model systems between the projects.